@Chiru, Если тебе интересно вот что я нашёл I've been checking out, and here is the only stuff I could find(As of 10th of November, 2024):

The author/artist is still active on both Pixiv(真田ジューイチ) & Twitter(sanadaeleven)

• Last active on Twitter, 24th June 2024, a post where they typed the lyrics of "Shikanoko Nokonoko Koshitantan". Posting around every three to four months

• Last active on Pixiv, 4th February 2024, a bunny girl art. Posting around once every one to two years

2. It's probably safe to say they are no longer an author now, as checking most animanga sites related to "KATOU Haruaki" shows that Abnormal-kei Joshi is actually one of their more recent works, and is still discontinued to this day. They are probably only drawing for their passion now and is hopefully doing well in another field.